• I think you're striving for a master-detail report style: Here's an idea

    Try using a list data region, grouping by Account, and add your two tables within the list region. Here's a link that illustrates the technique:

    http://jesborland.wordpress.com/2010/11/17/the-power-of-reporting-services-–-lists/

    Also, here's a link to nesting data regions in SSRS:

    http://msdn.microsoft.com/en-us/library/cc627449(v=sql.100).aspx

    Lastly, one other link that might help:

    http://technet.microsoft.com/en-us/library/dd239330(v=sql.105).aspx